The Nongovernmental International Panel on Climate Change (NIPCC) released an 880-page book challenging the scientific basis of concerns that global warming is either man-made or would have harmful effects.  

This extensive rebuttal of the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), three years in the making, was released in June 2009 by The Heartland Institute. Coauthored and edited by S. Fred Singer, Ph.D., and Craig Idso, Ph.D., the report is a comprehensive rebuttal of the Working Group I contribution to the Fourth Assessment Report (2007) of the Intergovernmental Panel on Climate Change (IPCC). The report, produced with contributions and reviews by an international coalition of scientists, provides an independent examination of the evidence available on the causes and consequences of climate change in the published, peer-reviewed literature examined without bias and selectivity. It includes many research papers ignored by the Intergovernmental Panel on Climate Change (IPCC), plus additional scientific results that became available after the IPCC deadline of May 2006.